In addition to a legitimate medical concept, the microbiome is a huge trend that’s spurred countless books, supplements, diet trends and even at-home testing kits. Now, it looks like that trend is officially here to stay.

This week, Merriam-Webster added “microbiome” to the English dictionary, defining the noun as “a community of microorganisms (such as bacteria, fungi, and viruses) that inhabit a particular environment and especially the collection of microorganisms living in or on the human body.”